perf(stringutil): optimize Format
#1583
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jakebailey
reviewed
Aug 14, 2025
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| var placeholderRegexp = regexp.MustCompile(`{(\d+)}`) | ||
| const maxInt = int(^uint(0) >> 1) |
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I'd eliminate this and just use math.MaxInt.
jakebailey
reviewed
Aug 14, 2025
| var b strings.Builder | ||
| b.Grow(len(text) + len(text)/4) | ||
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| for i := 0; i < len(text); { |
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I feel wary about the amount of code used here; it's a lot of string/index finagling.
Can this instead be replaced by a loop where we use strings.IndexByte or strings.Cut to find the next { or }, along with slicing text as we go along?
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A bit surprised this matters, given your profile only shows this taking a fraction of a percent? |
yeah we can probably close this. i just noticed this sticking out at me in the flame graph. but it is only a fraction of wall time |
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This PR improves the performance of
stringutils::Format, by removing the slow regex, in favour of a manual implementation.